The wizarding world may shine brightly with flying broomsticks, duels of magic, and bottomless butterbeer, but under all the fantasy is a darker reality—it’s filled with secrets, broken hearts, and betrayals that cut deeper than a wayward Bludger. Some are a shock, others quietly shattering, but all of them made their mark on Harry’s tale. From double-crosses of stealth to desperate acts of sorrow, here’s a countdown of the ten greatest betrayals in the Harry Potter series—beginning with the lesser stings and culminating in the greatest treachery.
10. Snape’s Secret Triple-Agency
For years, Severus Snape was the king of mixed messages at Hogwarts. Was he faithful? Was he a bad guy? The reality proved to be more complex—and more surprising—than anyone supposed. While Voldemort trusted him more than nearly anybody, Snape was secretly reporting to Dumbledore. While simultaneously making Voldemort believe he was double-crossing Dumbledore. That bit of multitasking was the secret to Harry’s ultimate triumph, and one of the most brain-twisting plot turns in the entire series.
9. Narcissa Malfoy’s Lie to Voldemort
At the Battle of Hogwarts, Narcissa Malfoy’s love for her son overshadowed the fear of the Dark Lord. Discovering Harry to be alive in the Forbidden Forest, she lied to Voldemort and reported him dead—putting everything on the line for the sake of her son. She wasn’t acting out of the greater good, but she provided Harry with the window he had to come back and complete the battle.
8. Regulus Black’s Rebellion against Voldemort
Sirius’ little brother, Regulus, didn’t make a lot of fuss in the main plot, but his subtle rebellion altered everything. Following what he witnessed of Voldemort’s cruelty—particularly towards Kreacher—he pilfered one of Voldemort’s Horcruxes as an act of sheer defiance. It got him killed, but his bravery laid the groundwork for Voldemort’s demise.
7. Kreacher’s Involvement in Sirius’s Death
Kreacher was bound to serve the Black family, but that duty came at the price of Sirius’s life. By feeding Voldemort’s side just enough information, he directly contributed to leading Harry to the Ministry of Magic. Although Kreacher eventually redeemed himself, fans still remember this as one of the greatest betrayals in the series.
6. Karkaroff Naming Names
When Voldemort died the first time, Igor Karkaroff saved his neck by revealing fellow Death Eaters to the Ministry. It kept him out of Azkaban… for a while. When the Dark Lord revived, Karkaroff’s treachery caught up with him, and he got the ultimate punishment.
5. Marietta Edgecombe Betraying Dumbledore’s Army
Oftentimes, betrayal originates from within the circle. Marietta Edgecombe, grudgingly going to Dumbledore’s Army meetings, betrayed them to Umbridge. What she did nearly killed the group and put Dumbledore in grave danger. Due to Hermione’s witty curse, she couldn’t reveal everything—but the friendship damage, particularly with Cho, had already been done.
4. Griphook’s Vault Double-Cross
Griphook had agreed to assist Harry, Ron, and Hermione in infiltrating the Gringotts vault of Bellatrix Lestrange… but he wasn’t necessarily in it for the camaraderie. The moment he had the Sword of Gryffindor in his possession, he tipped off the bank and left the three to their own devices. It was a brutal reminder that not everyone’s friendship in the wizarding world rests on trust.
3. Xenophilius Lovegood’s Desperate Betrayal
Xenophilius Lovegood loved his daughter Luna—but that love led him to betray Harry, Ron, and Hermione. In the hope of reclaiming Luna from the Death Eaters, he attempted to surrender the trio. It was a poignant moment, demonstrating how desperation and fear can distort even good people’s decisions.
2. Ron Walking Away from Harry
The Golden Trio wasn’t always unbreakable. Frustrated and overwhelmed, Ron ditched Harry and Hermione amid their Horcrux search. It wasn’t permanent—he returned—but it was a raw, human moment that cracked their trust and illustrated exactly how much pressure they were all under.
1. Pettigrew’s Ultimate Betrayal
The worst betrayal in the series belongs to Peter Pettigrew. As a friend of James Potter and Secret Keeper, he betrayed the Potters by giving away their whereabouts to Voldemort, killing them, and leaving Harry an orphan. His decision triggered almost all the tragedies in the series. Even after several decades, it is difficult to imagine a lower act.
Harry Potter betrayal isn’t so much about villains twisting the knife—it’s more about loyalty fraying under the pressure of fear, ambition, or love. These instances do hurt, but they also make the story deeper, reminding us that in life and magic, trust is tenuous and every decision counts.